It is the ultimate objective of this research team to develop a mathematical model of the foot structure that is sensitive to aberrant function and can be used to plan more effective conservative and surgical treatments. The mission of the NICHD is to ensure the health, productivity, independence, and well-being of all people through optimal rehabilitation. The proposed forefoot model would be useful as a guide to Podiatric physicians, Orthopedic surgeons, Physiatrists, and Physical Therapists to optimize treatment strategies in order to better rehabilitate patients. This project will focus upon three specific aims: (A) to develop a structural model of the forefoot from radiographic and 3D digital pointer based input data and demonstrate concurrent validity, (B) to develop a normative database of model parameters and associated foot function during gait for asymptomatic healthy individuals and stratify across foot type (i.e. pes planus, rectus, and pes cavus), and (C) to distinguish the model parameters and foot function for a group of patients with diabetes and hallux abducto valgus (HAV) from that of healthy. Improved understanding of the pathomechanics that afflict pes planus (e.g. HAV, Hallux limitus, osteoarthritis, tendonitis, plantar fasciitis, neuroma, posterior tibial dysfunction, chronic keratomata, collapsing pes valgus.etc) and pes cavus (e.g. hammertoes, tailor bunion, metatarsalgia, diabetic neuropathy, etc.) feet is needed. The proposed model of forefoot geometry is expected to be sensitive to different foot structures (and associated pathologies) and hence be predictive of commensurate foot function. Based upon positive findings from this investigation subsequent studies will be conducted to use the model as a tool for clinical decision making. Individuals with diabetes and lack of sensation may develop limb threatening wounds beneath their feet. If an ulcer forms and does not heel quickly an infection may ensue. If not successfully treated this infection could result in gangrene and the necessity for amputation. One goal of the proposed model is to predict the abnormally high pressures beneath these patients' feet so as to alert clinicians and suggest a course of action. [unreadable] [unreadable]